Using !mdn takes you to a mediocre-at-best MDN search page, not a specific page. My experience is that you’ll get better results from just adding the “mdn” keyword to the query and jumping to the first result—that is, instead of, say, `mix-blend-mode !mdn` (which takes you to https://developer.mozilla.org/en-US/search?q=mix-blend-mode), `mix-blend-mode mdn !` (which takes you to https://developer.mozilla.org/en-US/docs/Web/CSS/mix-blend-m... the ! to skip the results page and go to the first match can be at the start or end of the entire query). This technique doesn’t guarantee you’ll end up on MDN, but for realistic queries you’re almost certain to.